A chip fan created to fit on the ER11 collet on my 3020 CNC machine. This is intended to be a very snug fit. Included is STLs for clockwise and counter clockwise rotation.
This was tested up to 8000RPM on my machine with no issues.
Printed at 0.2 for me but others should be OK.
Should work fine with other machines. A minor amount of scaling may be required depending on your machine and filament.
The CAD model was created with Rhino3D.